Formerly called Swine Flu) H1N1 A Virus is a virus which is in a imminent pandemic phase which is Phase 5. Influenza A is one of the classifications of seasonal influenza.
Let's review what viruses are.
Virus- were originally distinguished from other infectious agents because they are especially small (filterable) adn because they are obligatory intracellular parasites.
Obligatory Intracellular Parasites (OIP)- are parasites which absolutely require living host cells in order to multiply.
Viruses are alive inside the cell but dead outside the cell.
Parts of a Virus
1) Nucleic Acid - They were first discovered in the nuclei of cells.
There are 2 kinds of Nucleic Acid:
1.1) Deoxyribonucleic Acid (DNA)- is an organic molecule which consists of a double helix and 4 elements (Thymine, Adenine, Cytosine and Guanine).
1.2) Ribonucleic Acid (RNA)- is an organic molecule which consists of a single helix also with 4 elements (Uracil, A,C,G).
NOTE: The virus can't have both nucleic acids.
2) Capsid- is a protein coat which surrounds the nucleic acid. The structure is ultimately determined by the viral nucleic acid and acoounts for most of the viral mass.
2.1) Capsomere- Protein Subunits of a capsid
2.2) Envelope- In some viruses, this covers the capsid. It usually consists of some combination of lipids, proteins, and carbohydrates.
2.3) Spikes- Carbohydrate-Protein complexes that project from the surface of the envelope.
Types of Spikes for the Influenzavirus
2.3.1) Hemagglutinin Spikes (H)- Agglutination of erythrocytes (Red Blood Cells) that occurs when the viruses are mixed with them. There are about 300 H spikes.
2.3.1.1) Agglutination- Clumping of Cells
2.3.2) Neuraminidase Spikes (N)- They enzymatically help the virus separate from the infected cell as the virus exits after intercellular reproduction. It also stimulates the formation of antibodies. There are about 100 N spikes.
Antigen (Immunogen)- Any substance that causes antibody formation and reacts only with its specific antibody
Antibody (Immunoglobulins)- A protein produced by the body in response to an antigen, and capable of combining specifically with that antigen.
In this case, The H1N1 virus stimulates the formation of the IgG (1 of 5 types of Immunoglobulins) which is a monomer (simplest molecular structure of a bivalent immunoglobulins)
"Viral strains are identified by variation in the H and N immunogens. The different forms of the immunogens are assigned numbers- For example, H1, H2, H3, N1, and N2. Each number change represensts a substantial alteration in the protein composition of the spike. These changes are called Antigenic Shifts (Immunogenic Shifts)"
Antigenic Drifts (Immunogenic Drifts)- A minor variation in the antigenic makeup of influenza viruses that occurs with time.
Souce: MICROBIOLOGY: AN INTRODUCTION, 8th Edition by TORTORA, GERARD J.; FUNKE, BERDELL R.; CASE, CHRISTINE L., published by PEARSON EDUCATION SOUTH ASIA PTE. LTD.
Classification of the H1N1 Virus
1) Viral Family - Orthomyxoviridae
2) Viral Genus - Influenzavirus A
3) Morphology- Enveloped Helical
4) Viral Species- Influenza A Virus
5) Viral Serotype- H1N1 (00.046.0.01.001.00.001. -Decimal Code)
For more info about Viruses, go here: http://www.kcom.edu/faculty/chamberlain/Website/Lects/PROPERT.HTM
Connection with the Pandemic Spanish Flu of 1918
In 1918, the Spanish Influenza was a pandemic that infected about 50 million people. They say the origin is in Northeastern US. It carries the H1N1 serotype but may have the different genetic composition as the H1N1 A Virus of 2009. It was the worst outbreak of influenza known.
The virus now started at Mexico on March, 2009. It spreaded to everywhere already. The 1918 Spanish Flu was in Phase 6, since it was a pandemic.
Instead of calling it Swine Flu, we should call it H1N1 Virus (According to WHO) to remove the pigs out of bias. I must say that it is legitimate to call it Spanish Influenza II Virus because it is the same virus but a different strain.
Pandemic- is an epidemic in a global scale.
Epidemic- occurs when new cases of a certain disease occur in a given human population, during a given period, substantially exceed what is "expected," based on recent experience.
So to speak, the 1918 pandemic faded at 1919. If history repeats itself, the WHO, CDC and other health agencies will do their best to prevent it. The technology now didn't exist in the technology then.
Q: How did the strain from 1918 return in 2009?
There was a possibility of the virus transmission from a corpse to a pig in Mexico. The data with this question is insufficient. The only evidence are the similarity of the strain and the epidemiological consequences of the strain.
Are Face masks effective?
"The authorities are beginning to acknowledge that face masks will do more to protect other people from your germs, then it will to protect you from other peoples' germs. Reason is that like dust and allergens, against which a mask works for exactly 20 minutes, germs build up on the face mask, and pretty soon you're breathing concentrated germs off the mask itself. It can help protect you from a sudden spray of germs in the face on a bus trip downtown." According to someone in the Microbiology Yahoo! Groups.
Q&A about H1N1 Virus by CNN
(CNN) -- The World Health Organization has called it a "public health emergency of international concern."
Seemingly out of nowhere, the swine flu virus has spread from person to person in Mexico and the United States, triggering global concerns as governments scramble to find ways to prevent further outbreak.
Q. What is swine flu?
A. Swine influenza, or flu, is a contagious respiratory disease that affects pigs. It is caused by a type-A influenza virus. Outbreaks in pigs occur year-round.
The most common version is H1N1. The current strain is a new variation of an H1N1 virus, which is a mix of human and animal versions.
Q. Does swine flu affect humans?
A. While the virus causes regular outbreaks in pigs, people usually are not struck by swine flu. However, there have been instances of the virus spreading to people -- and then from one person to another. The only difference is, says the CDC, transmission in the past did not spread beyond three people -- as it has done this time.
Q. What is behind the spread of the virus this time?
A. Researchers do not know yet know. People usually get swine flu from infected pigs. For example, farmers handling infected pigs can contract the virus. However, some human cases have occurred without contact with pigs or places they inhabited.
Q. What are the symptoms of swine flu?
A. The symptoms are similar to the common flu. They include fever, lethargy, lack of appetite, coughing, runny nose, sore throat, nausea, vomiting and diarrhea.
Q. How does the virus spread?
A. The virus spreads the same way the seasonal flu does. When an infected person coughs or sneezes around another person, the latter is put at risk. People can become infected by touching something with the flu virus on it and then touching their mouth, nose or eyes. An infected person can pass the virus to another before any symptoms even develop.
Q. Why is this spread troubling?
A. Scientists are concerned whenever a new virus is able to jump from an animal to a person -- and then spread from person to person. When the flu spreads person to person, it can continue to mutate, making it harder to treat or fight off.
The World Health Organization has said the current outbreak has "pandemic potential," and has urged governments to take precautions to prevent its spread. If the virus continues to mutate, drug makers won't be able to come up with vaccines fast enough.
Q. Can swine flu be fatal?
A. Just like the regular flu, swine flu worsens pre-existing medical conditions in people. So people with already compromised immune systems can die after contracting it.
Q. But doesn't the common flu kill more people?
A. Yes, common seasonal flu kills 250,000 to 500,000 people every year. But what worries officials is that a new strain of the flu virus can spread fast because people do not have natural immunity and vaccines can take months to develop.
Q. Have there been swine flu outbreaks in the past?
A. From 2005 to January 2009, 12 human cases of swine flu were detected in the United States, without deaths occurring, the CDC said. In September 1988, a healthy 32-year-old pregnant woman in Wisconsin was hospitalized for pneumonia after being infected with swine flu and died a week later. And in 1976, a swine flu outbreak in Fort Dix, New Jersey, caused more than 200 illnesses and one death.
Q. What does the World Health Organization mean when it says swine flu has "pandemic potential"?
A. If the virus spreads over a wide geographic area and affects a large segment of the population, it is upgraded from an "epidemic" to a "pandemic."
Q. How deadly have pandemics been in the past?
A. In 1968, a "Hong Kong" flu pandemic killed about 1 million people worldwide. And in 1918, a "Spanish" flu pandemic killed as many as 100 million people.
Q. How can one keep from getting swine flu?
A. There are no vaccines available. But several everyday steps can help prevent the spread of germs: Washing hands frequently; avoiding close contact with people who are sick; and avoiding touching surfaces that might be contaminated.
Q. Are there medicines to treat swine flu?
A. Yes, the CDC recommends using anti-viral drugs. They keep the virus from reproducing inside the body. And in an infected person, the drugs make the illness milder.
Q. Can one contract swine flu from eating or preparing pork?
A. No. Pork and other pig-derived products, if properly handled and cooked, do not transmit swine flu. The flu virus is killed by cooking temperatures of 160°F (70°C).
"The Legacy of the Pandemic
No one knows exactly how many people died during the 1918-1919 influenza pandemic. During the 1920s, researchers estimated that 21.5 million people died as a result of the 1918-1919 pandemic. More recent estimates have estimated global mortality from the 1918-1919 pandemic at anywhere between 30 and 50 million. An estimated 675,000 Americans were among the dead."
Source: http://1918.pandemicflu.gov/the_pandemic/index.htm"
There are many pre-cautions and pls. do not go to the H1N1 infected countries. God Bless all and be updated always.
Remember, As I type, the epidemic is pandemic imminent.
Update: http://news.yahoo.com/s/livescience/20090501/sc_livescience/worstcasescenarioforfluestimated
PS: I corrected that no 2 viruses can have the exactly the same genetic composition. So, therefore it is a very different strain.
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